Question

Find the difference of air pressure between the inside and outside of a soap bubble $5mm$ in diameter, if the surface tension is $1.6N/m$.

• A. $2560N/m^2$
• B. $3720N/m^2$
• C. $1208N/m^2$
• D. $950N/m^2$

Answer 1

The correct option is A $2560N/m^2$

$\rho =\frac{4T}{R}=\frac{4\times 1.6}{2.5\times {10}^{-3}}$

$=2560N/m^2$